﻿using System;
using System.Globalization;
using System.Linq;
using System.Text.RegularExpressions;
using Xbim.Ifc4.Interfaces;
// ReSharper disable NonReadonlyMemberInGetHashCode

namespace Xbim.Ifc
{

    /// <summary>
    /// Represents a Colour in the model
    /// </summary>
    
    public class XbimColour
    {     
        /// <summary>
        /// Gets or sets Colour Name, defaults to its parts
        /// </summary>
        
        public String Name
        {
            get { if (string.IsNullOrWhiteSpace(_name)) return ""; else  return _name; }
            set { _name = value; }
        }

        public override bool Equals(object obj)
        {
           
            XbimColour col = obj as XbimColour;
            float tolerance = (float) 1e-5;
            if (col == null) return false;
            return Math.Abs(col.Red - Red) < tolerance &&
                    Math.Abs(col.Green - Green) < tolerance &&
                    Math.Abs(col.Blue - Blue) < tolerance &&
                    Math.Abs(col.Alpha - Alpha) < tolerance &&
                    Math.Abs(col.DiffuseFactor - DiffuseFactor) < tolerance &&
                    Math.Abs(col.TransmissionFactor - TransmissionFactor) < tolerance &&
                    Math.Abs(col.DiffuseTransmissionFactor - DiffuseTransmissionFactor) < tolerance &&
                    Math.Abs(col.ReflectionFactor - ReflectionFactor) < tolerance &&
                    Math.Abs(col.SpecularFactor - SpecularFactor) < tolerance;    
        }

        public override int GetHashCode()
        {
           
            return Red.GetHashCode() ^ Green.GetHashCode() ^ Blue.GetHashCode() ^ Alpha.GetHashCode() ^ DiffuseFactor.GetHashCode() ^
                TransmissionFactor.GetHashCode() ^ DiffuseTransmissionFactor.GetHashCode() ^ ReflectionFactor.GetHashCode() ^ SpecularFactor.GetHashCode();
        }

        /// <summary>
        /// True if the cuolour is not opaque
        /// </summary>
       
        public bool IsTransparent
        {
            get
            {
                return Alpha < 1;
            }
        }
        /// <summary>
        /// Default constructor
        /// </summary>
        public XbimColour()
        {
           
        }

        /// <summary>
        /// Constructor for Material
        /// </summary>
        /// <param name="name">Material Name</param>
        /// <param name="red">Red component Value (range 0 to 1.0 inclusive)</param>
        /// <param name="green">Green Value (range 0 to 1.0 inclusive)</param>
        /// <param name="blue">Blue Value (range 0 to 1.0 inclusive)</param>
        /// <param name="alpha">Alpha Value (range 0 to 1.0 inclusive)</param>
        public XbimColour(string name, float red, float green, float blue, float alpha = 1.0f)
        {
            Name = name;
            Red = red;
            Green = green;
            Blue = blue;
            Alpha = alpha;
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="name">Material Name</param>
        /// <param name="red">Red Value in range 0.0 to 1.0</param>
        /// <param name="green">Green Value in range 0.0 to 1.0</param>
        /// <param name="blue">Blue Value in range 0.0 to 1.0</param>
        /// <param name="alpha">Alpha Value in range 0.0 to 1.0</param>
        public XbimColour(string name, double red, double green, double blue, double alpha = 1.0)
            : this(name, (float)red, (float)green, (float)blue, (float)alpha)
        {
        }

        /// <summary>
        /// Creates a colour from Hue, Saturation and Value
        /// </summary>
        /// <param name="name">Color name</param>
        /// <param name="hue">range 0..360</param>
        /// <param name="saturation">range 0..1</param>
        /// <param name="value">range 0..1</param>
        /// <returns></returns>
        // ReSharper disable once InconsistentNaming
        public static XbimColour FromHSV(string name, double hue, double saturation, double value)
        {
            int hi = Convert.ToInt32(Math.Floor(hue / 60)) % 6;
            double f = hue / 60 - Math.Floor(hue / 60);

            // value = value * 255;
            var v = Convert.ToDouble(value);
            var p = Convert.ToDouble(value * (1 - saturation));
            var q = Convert.ToDouble(value * (1 - f * saturation));
            var t = Convert.ToDouble(value * (1 - (1 - f) * saturation));

            if (hi == 0)
                return new XbimColour(name, v, t, p);
            else if (hi == 1)
                return new XbimColour(name, q, v, p);
            else if (hi == 2)
                return new XbimColour(name, p, v, t);
            else if (hi == 3)
                return new XbimColour(name, p, q, v);
            else if (hi == 4)
                return new XbimColour(name, t, p, v);
            else
                return new XbimColour(name, v, p, q);
        }

        /// <summary>
        /// Gets or sets Red component Value in range from 0.0 to 1.0
        /// </summary>
       
        public float Red
        {
            get;
            set;
        }

        /// <summary>
        /// Gets or sets Green component Value in range from 0.0 to 1.0
        /// </summary>
       
        public float Green
        {
            get;
            set;
        }

        /// <summary>
        /// Gets or sets Blue component Value in range from 0.0 to 1.0
        /// </summary>
       
        public float Blue
        {
            get;
            set;
        }

        /// <summary>
        /// Gets or sets transparency component Value in range from 0.0 to 1.0.
        /// A value of 0.0 is completely transparent.
        /// A value of 1.0 makes the colour fully opaque
        /// </summary>
        
        public float Alpha
        {
            get;
            set;
        }

        private String _name;
        
        public readonly float DiffuseFactor;
        
        public readonly float TransmissionFactor;
       
        public float DiffuseTransmissionFactor;
        
        public readonly float ReflectionFactor;
       
        public readonly float SpecularFactor;
        
        /// <summary>
        /// Returns a <see cref="System.String"/> that represents the value of this instance, ignoring the name.
        /// </summary>
        /// <returns>
        /// A <see cref="System.String"/> that represents this instance; it can be used for persistence across invariante cultures if the name is not needed.
        /// </returns>
        public override string ToString()
        {
            return string.Format(CultureInfo.InvariantCulture, "R:{0:r} G:{1:r} B:{2:r} A:{3:r} DF:{4:r} TF:{5:r} DTF:{6:r} RF:{7:r} SF:{8:r}",
                Red, Green, Blue, Alpha, DiffuseFactor, TransmissionFactor, DiffuseTransmissionFactor, ReflectionFactor, SpecularFactor);
        }

        public static XbimColour FromString(string source)
        {
            // for legacy compatibility we replace comma with dot (old versions of the ToString function used local culture).
            //
            source = source.Replace(',', '.');
            var colRegex = new Regex("R:([\\d.]+) G:([\\d.]+) B:([\\d.]+) A:([\\d.]+)( DF:([\\d.]+) TF:([\\d.]+) DTF:([\\d.]+) RF:([\\d.]+) SF:([\\d.]+))*");

            var m = colRegex.Match(source);
            if (!m.Success)
                return DefaultColour;
            var red = float.Parse(m.Groups[1].Value, CultureInfo.InvariantCulture);
            var green = float.Parse(m.Groups[2].Value, CultureInfo.InvariantCulture);
            var blue = float.Parse(m.Groups[3].Value, CultureInfo.InvariantCulture);
            var alpha = float.Parse(m.Groups[4].Value, CultureInfo.InvariantCulture);

            if (m.Groups[5].Value == string.Empty)
                return new XbimColour(red, green, blue, alpha);

            var diffuseFactor = float.Parse(m.Groups[6].Value, CultureInfo.InvariantCulture);
            var transmissionFactor = float.Parse(m.Groups[7].Value, CultureInfo.InvariantCulture);
            var diffuseTransmissionFactor = float.Parse(m.Groups[8].Value, CultureInfo.InvariantCulture);
            var reflectionFactor = float.Parse(m.Groups[9].Value, CultureInfo.InvariantCulture);
            var specularFactor = float.Parse(m.Groups[10].Value, CultureInfo.InvariantCulture);

            return new XbimColour(red, green, blue, alpha, diffuseFactor, transmissionFactor, diffuseTransmissionFactor, reflectionFactor, specularFactor);
        }


        public static readonly XbimColour DefaultColour;
        
        static XbimColour()
        {
            DefaultColour = new XbimColour("Default", 1, 1, 1);
        }

        public XbimColour(IIfcSurfaceStyle style)
        {
            var rendering = style.Styles.OfType<IIfcSurfaceStyleShading>().FirstOrDefault();
            if (rendering != null)
            {
                var rgb = rendering.SurfaceColour;
                Red = (float)rgb.Red;
                Green = (float)rgb.Green;
                Blue = (float)rgb.Blue;
                Alpha = (float)(1.0 - rendering.Transparency ?? 1.0);
            }
        }

        internal XbimColour(IIfcColourRgb rgbColour)
        {
            Red = (float)rgbColour.Red;
            Green = (float)rgbColour.Green;
            Blue = (float)rgbColour.Blue;
            Alpha = 1;
        }

        public XbimColour(IIfcColourRgb ifcColourRgb, double opacity = 1.0, double diffuseFactor = 1.0 , double specularFactor = 0.0, double transmissionFactor = 1.0, double reflectanceFactor = 0.0)
            :this(ifcColourRgb)
        {
            Alpha = (float)opacity;
            DiffuseFactor = (float)diffuseFactor;
            SpecularFactor = (float)specularFactor;
            TransmissionFactor = (float)transmissionFactor;
            ReflectionFactor = (float)reflectanceFactor;
        }

        public XbimColour(float red, float green, float blue, float alpha = 1.0f, float diffuseFactor = 1.0f, float transmissionFactor = 1.0f, float diffuseTransmissionFactor = 1.0f, float reflectionFactor = 0.0f, float specularFactor = 0.0f)
        {
            Red = red;
            Green = green;
            Blue = blue;
            Alpha = alpha;
            DiffuseFactor = diffuseFactor;
            TransmissionFactor = transmissionFactor;
            DiffuseTransmissionFactor = diffuseTransmissionFactor;
            ReflectionFactor = reflectionFactor;
            SpecularFactor = specularFactor;
        }
    }
}

